Use a Midspan not a POE Switch!

Successfully future-proofing your network environment includes achieving cost and functional efficiencies, particularly in today’s economy. A balanced network needs to provide compatibility, expandability, and flexibility to support a vast number of new and emerging Ethernet devices with various power requirements. The most effective and practical solution is “power-on-demand” midspan technology.

Originally PoE switches were being deployed to power low-wattage endpoints such as VoIP phones, wireless access points, and entry-level IP security cameras. Today, many of these devices have evolved into more advanced solutions with specific power requirements. Feature-rich VoIP phones that offer color video-conferencing, next-generation security cameras, larger-area wireless access points, PC workstations, and other devices require reliable higher power over an existing Ethernet infrastructure. The old approach was to endure a “forklift upgrade” and buy new PoE switches at a considerable cost to meet these higher-power requirements. But today, it’s actually more efficient and less costly to separate your data and power devices. This will allow you to keep your best-in-class business switch for your IP needs and supplement it with best-in-class midspan technology to power the endpoints. You will achieve full power on every port, gain support for both the legacy PoE standard (IEEE802.3af) and the higher-power IEEE802.3at standard while providing greater flexibility for 75% less than the cost of replacing your business-class switch.

Power management in a PoE switch doesn’t cut it anymore
Today, most switches are merely PoE-enabled with the majority of those relying on power management to share available power across the switch ports. The switches are designed with a smaller power supply that is only capable of powering the switch itself and providing 15.4 watts of power on a limited number of ports to power a legacy IP phone or access point. The switch designers made the assumption that you wouldn’t need the full 15.4 watts per port and could get by with much less power, even though the IEEE 802.3af standard specifies differently.

Not enough power for ports
If a 24-port L2+, 200-watt, PoE-enabled switch in a 10-person call center uses 40 watts to power the switch, it has only 155 watts of power left to use across the 24 open ports. If the call center deploys 10 IP phones using 7 watts each, the switch provides 70 watts to power the phones with 85 watts remaining to share across the open 14 PoE ports. When the call center expands by deploying eight more phones with video capability, the new phones require 13 watts each for a total of 104 watts (only 85 watts available). Even though you have enough available ports, the switch cannot power all 18 phones.

Another example illustrating the limitations of a PoE Switch with power management involves a 24-port PoE switch with a 195-watt power supply. After the 40 watts needed to power the switch, you have approximately 155 watts available across the 24 ports to power endpoints. If 12 of the 24 ports are used to connect devices using 11.5 watts each, you would utilize 138 watts of the available 160, leaving only 17 watts to power the remaining empty 12 ports. This will not work and no longer serves the expansion needs of your network!

Based on the old “forklift upgrade” premise, these common examples would require the purchase of another L2+ 24-port PoE switch. This is unnecessary as a $500 midspan can provide more functionality with greater flexibility for even further expansion. Why would anyone spend more to get less and cause more bottlenecks in a network?

The preferred choice: power-on-demand midspans
The practicality of letting a switch do your network switching while utilizing a midspan to provide power-on-demand is made obvious especially when considering devices beyond basic VoIP phones. In the case of powering outdoor security cameras with heaters, motors, and Pan-Tilt-Zoom functions, the number of available ports no longer is the issue. If each camera requires 15W of power, it’s almost certain that a PoE-enabled, 200W switch will run out of available power before it runs out of ports.

Power management works when distributing different loads of power to specific ports on a PoE switch, but is pointless if there is not enough power for all the ports. IEEE PoE standards are allowing more and more devices with higher-power requirements to be powered over Ethernet. Rather than utilizing power management in a switch, the answer is a 400W midspan that can cost-effectively deliver 15.4 watts of power on every port and provides for instant network expansion. If you can get a 400W midspan for under $500, why would you pay $2,500 to $5,000 for a business-class L2+ network PoE switch only to get 24 ports, 195 watts for device use, and receive no additional switching benefits?

Not all midspans are created equal
When the time comes to future-proof your network, you need to know that all midspans are not the same.

To enhance your best-in-class network switch, select a best-in-class midspan. That means a midspan designed and manufactured by a proven power-supply company that understands power, understands your power needs, and delivers solutions on a system-wide, enterprise level. Why buy a midspan from a company whose core focus is merely chips when you can buy it from a manufacturer with a proven track record in energy-efficient and enterprise power products that focuses on power supplies?

Select a midspan manufacturer that has multiple members on the IEEE PoE committee helping to define safe, new PoE standards. This ensures that every midspan is designed to meet current and future IEEE specifications. Most importantly, it also means the midspans produced today will accommodate the requirements for the next generation of IEEE specifications and provide for backward compatibility to support legacy equipment.

For better quality and cost control, select a midspan manufacturer that manufactures its own product rather than outsourcing across the globe. Select a manufacturer that designs and tests its products in the United States allowing for greater focus on emerging technology and on the North American PoE market needs.

Competitive pricing doesn’t just mean the midspan is less expensive than a switch. It means it is more cost-effective than other midspan products on the market making it much more competitive for future applications and designs. For the best pricing structure, select a manufacturer that designs, manufactures and tests its products in-house rather than relying on a third-party manufacturer faced with rising costs and cost-cutting measures.

Look for midspans that have USB connectivity for the management console. These are much more user-friendly and field-practical than the midspans requiring special adapters for compatibility with RS-232 jacks.

Select midspans designed around an open silicon platform allowing them to operate with multiple best-in-class vendor PoE chips. Midspans that use a single vendor’s proprietary chip can limit flexibility with respect to cost, features, functionality and scalability. Who likes proprietary?

For the greatest flexibility, choose a midspan that natively supports 10/100/1000 (Gigabit) Ethernet.

A midspan that offers full power (802.3af, 15.4 watts and/or 802.3at, 30 watts) per port is the best choice for future-proofing your network because no matter what end device you want to add—more phones with more functionality, security cameras with advanced functionality, PC workstations—the power is available. As more devices are supported by the increased standards such as IEEE 802.3at and beyond, midspans give you options, flexibility, and cost savings. Need 30, 60, or 120 watts of PoE power-on-demand but you’re not sure where to get it? Talk to the leader in advancing PoE technology—Phihong, the name behind

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